SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0cb19949b82bba9388cfee3283886c1aabca9ebf61ad1867011b92c51ecb911e' 
  AND token = 'MpxFon/MWNrQ7J+PBES4NMmiCNWEz8rY4hTbGEIBcds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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