SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaa41db3be4fd9687a6931be71334739fbb9b686925aa0f5d90695d024b7c862' 
  AND token = 'ELvGt8NP+cXX3IYCvnZpyodZbr1wICHwIrBLAix0S+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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