SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4a3e7ab3f5cf963eccdb83d2a3a514036aa845e83ac4c1ba36cc9e3efa8c0c6' 
  AND token = 'T14NXgDcFMcK2od1DkygKSUWENguBQTE8Kxq0ba7EwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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