SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a2b02685ffc99a749a120d5146be851076c5b1ea71f3a0015768b90026dd90dd' 
  AND token = 'ZAxyrOZAXIDBFF/8wENFhZbtlv4Q5T3E3P1+8d8iKks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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