SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '490de0df9c59ee35a588de7b66fe5b73a7ead267d779301eb25afbb19d0bcdca' 
  AND token = 'EY9Vu7DtADHxYqZn1U4szzdZTM/M97m/uEOysALTvAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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