SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e11dfebcd145a3d56b10f2b73c5692a535cbe16122ffc33c14ff9c8ed6a4f244' 
  AND token = 'o8EbuSdyUAAl+t9JvCNRgOVf2W8siuQvynPXGqjhOmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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