SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7a13301c2389d317b241e0028e1a7239d6cc970b47ddd2c381c74667d1a91a4' 
  AND token = 'OE25UtI7panYY4/FpYXvhdD2rFeUqbmj0SpnQlnbMcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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