SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd53c3002a00c73136b942642dccb2cb2638180f8720132f796732dc8ac87f9ff' 
  AND token = 'TalSbWCDdBHtGkmcOoiVg3STFj5X+XMyTEM+WFGIHR4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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