SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b7a1c50b45390673b18043d379a3b4374612689d83709732af2bd053b8c992f' 
  AND token = 'yPtIGAuDulBVL8BHLx00C2FD/hflj1I7HQnbTQwR128=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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