SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5cff82d4aec6b46209ea5a9e9b27db10d1fce3b59ce5b996bed5bf7779507d6' 
  AND token = '9ciqXJms9/dUUY3+kBH4czPw37253FKTRhm3yleWFSE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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