SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e67a47f036a935383fb5e4a0bfaf7ea3f8b74e504b7b09444a98d3487e53ff14' 
  AND token = 'i7kapo7bEplYC1zgCxpJJ9C39temx82uQmQTfW6ldYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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