SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2b50ef4d0be7984f518cad6b93a69a52ae20a51a0f4f2dadd22e1ffe918bfeb' 
  AND token = 'hIFt90nVN+FRbOfuoNnaqz666JBo4t7P0ss4/tMaj0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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