SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e5010ddbd506c4341fdc590f3b9379757569c14d5dc4e9af5fcd8f9e623f1746' 
  AND token = 'tI2HrhkosZ5AjWKhwXRSAg09Rwi/OSJhTduAGvXj/BU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}