SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8060a54dcae409c18512879aec1c943d9ee50b6800ba8a8a2e1f0b18883ec0c3' 
  AND token = 'MMwN6LycHbOMJHV5kzQSo5zSekz0UipO2UyUd43s6VM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}