SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '183368159d8aadb5e16f150c27792ef276c2dd0ec03c253bba02eb75754101b7' 
  AND token = '4PDrJrudjuvtwVSUyA/C8Iu684egJWzdvnKfYhn1BaY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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