SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97159b9d08bd16e5c25d749c9384a329b1da857e3b448b2f525454415c11a53c' 
  AND token = 'J+TsKgJedfdxYNGwYO9l+JcP/9RBb5R3zhByg1Gj1LE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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