SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8d65b1a673f785d76654c28fef72ca3d0ff289386f844b2d6433853ae03a5ce' 
  AND token = 'idJA6Kv+ygJVTgLp+z8w/SGp9sbOXDBzob6KDJqQwdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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