SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '957df00e8b1b26017117411d8f6d4b5e92875580e469eaa9560eb9393b021067' 
  AND token = 'zYBjqegZTWcXwZJVtEO4zVK+6qY65algQzbzsHBDa8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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