SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fa305ff8639554da89f227caa1eed5ffcf280cba0a2a610b0d436e1eb3e6fe0' 
  AND token = 'hObJCqZ7fWqZ96gN4BMsSedWSlRzvXyvp+KiwE9njlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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