SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ef73e8a77e49f65877dad31f9283e33fb0c7bedc7bc9e86d6f4c5d74aa3c2b1' 
  AND token = '1IGEQqjGVtcS56lBJzmaH6wnhVlqxsz5WkKaIaxSCJM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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