SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86767f77533a7fb9462e4245c8ed103bafb571a4246cadf09663db5873e778de' 
  AND token = '5Q5ChBDzPTlAk8fZzbj+ZBq8Hl5zkKlJ62Yd6HSNOZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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