SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a60983e403a84980f4b2426bd48223704e61fcd29345847f4df67d2c6932864' 
  AND token = 'c+3sEw3j1yM2lcZB5o1y5kw0BaekfuZYZry/+qc24cg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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