SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbad5ff34ba6b27c4e93078d4985de4b5396bae1a5c8f097dce2274ac3bbe061' 
  AND token = 'ws+mhvTJURCES0Lr84LxhIRbIvO/gKmJ+pxgkxaY6lw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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