SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'baa5a648b97caf089f50de6c7239a9af35a241b81c311808eccc6c2184a7ae34' 
  AND token = 'jOp530p03WlaznR1vCGQImH2/x7qJvjX1ALdQUTGVB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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