SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0ae4c676642e81aba5f9dc249da2ca072a4f06bb14d37bef8a09bfd21bb4213' 
  AND token = 'zAsko+/YxgdP9Jy2X3dXGf5c2KOEjkzx2ZpsqT2TPXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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