SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd44f8950cb66195b7e189ee46830c4d277620792385975d38bcc698750726eea' 
  AND token = 'lhPKOWdHregaSj9PgtWbuWl+ebBt0AuY67l1L4yHmd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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