SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8712d9555282f56c6b9b00b19ad63616d25922bc83196320a7963d383c0ad06b' 
  AND token = 'qVbACxZWLG8D6kmM3rw+FNhxQ3iDLNI88xKpcapctIY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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