SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '191b3cb6a03880f00aa8c78cfbd8562bcf6ee711d1a1d4c06763abdd99ab4bdf' 
  AND token = 'aM9eZin2ev1NUttWwEwBfPi4etJBIB4eq49rJxvgm/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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