SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9190ed0b216721a9b47dad994927d579f785e0302b0f0072a3ea7ec35efeda90' 
  AND token = 'dtKlrFbirF2QXciLoFThxVLpLCxx3yTtgjemLTDKLI4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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