SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c95e1174160db86e2626b9ab1995bacb853af96f2bef6a3687ffbc7992fad16' 
  AND token = 'M/hKuSDPpV5vlwa2eT61CqBVCUqvSWviIRrX3GO3ueg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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