SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a752dab024881d28cf2daa160318ed09ff3c6135019ab74378fdd117677a99f5' 
  AND token = 'vyFT8gjbI8taw/IkHPnM96jTCJ5E7jh4WZZclIrvmA4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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