SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0dc89678f9a33244885d647e40c333781a241dc30fa9213421dadb8e29eafaf' 
  AND token = '7AxKKyqdfOcdWeH0Dsj+AxdT9ouIUaZGcgaYQA7NsZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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