SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1432b2070e72ded2910b686acb4af965d3104d84bf1e9ea9d4b2d412e5ce2940' 
  AND token = 'l0+VpHZKhnbw5g56sZGzD9CkYIglHG7mNx6hv0O+wUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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