SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b906d7ce1cbe6e5dfad236f9536ba25a9a8cf617562082de05ffc0bb1522c362' 
  AND token = 'P4VlZldU3SWeKPaBCjl1if95QW7Z2/M2nG0qL2axFsU=' 
  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"
    }
  }
}