SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a829dd2bdcca7d06b50cfb8566a739bef7dbbc648f79f5770e8d33547c449edc' 
  AND token = 'G4I7C3lsHM3/1Zejw6dPZeRYdpBqH9VGn6BF2DJHssQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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