SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '02b64404be0d6d2c2f902838e45501e192920e4bf1275a3c4a37ee282c61b7d7' 
  AND token = 'OkEw13pe1//R/aG8mUfHxiPLG2oRMrhsmIDBivCw+UA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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