SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c613a5e423f3fab2e8b58d68c3bf557be4702d65fb99a6bb89bfecfea26e323e' 
  AND token = 'GT1ADzk4wzxp31wtm6osOP1dJWSmf8H9GtmXtdp5egY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}