SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '300631578e9e436c2324c3ad2f6e2adae0e15b89c35109b5ac18fa7b4f12a119' 
  AND token = 'ntwwRO6l0A+0wDIOrKNkGtk2hbbnicnKHLMBa7SQllQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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