SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c636ae04aa604f2917c9e167ce3e1cdf3617494985db5c2f9dc90c66e4775048' 
  AND token = 'S14qGTl5FEZ9zX52FzzkJOQqd+miVzaozmOuKw7W0y0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}