SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52454325ede7b774e3991e5376c29b52920855d8b32c438412960f5b3e1eb67c' 
  AND token = '9Oz3kPV4nPFSj5jqb2vdYFwod/UWCQ33TzpHiY2//GQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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