SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e190ffcd9d444d0ff8b8b177c00fe3b8e6770fb3148b391ab4dc622935132a98' 
  AND token = 'ArOpZapqnYTgwpYh036fYbw+usU1LhF4vfIZmyvMb8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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