SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed2a78543046d181e5409bd0afec784f59de6cad24193c636f66ddc5488f3fa5' 
  AND token = 'MPHRXyQ4q0HDqCIskxF+9UB8h7lweBQcSksuPKOBHZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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