SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f14d482ebcc9db212f819563497a45ef7c17ce57b51c7314ed23580685a491d3' 
  AND token = 'I2oZ9EnMxzOYX7mZPXfqmDtvAi4UpAVGDUkJARk9eJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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