SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c4c07e4a7d388ca9e9cf92f521d53e2d94f79f2084ef9b90306074ed1f649377' 
  AND token = 'zZqUfDN4AifLxxHr6kcSthHlKO2/kV+54hC7/jZbDaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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