SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c8293901a8ef5f454fc5b5e806f3ab0201e2565290a8844f57f9801256a5048c' 
  AND token = 'bRHM2aCXfDBO0jvkvVbiSEihSyMJrOsQ1BYgYJJmZgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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