SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c2bfa3f5e833b874559ec48038f5d306c437ea27ecdf4b169feb2695e3e7fe6' 
  AND token = 'Tz/YtDrczOJmBUenEOSShlUKpUV9kyqGqhOlgPJM0mM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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