SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c10fa53be3a16ae89f8b4638f347396eafb212b968a6da4ea0b5d657eaf8ca2' 
  AND token = 'zCNVbH0beogv1YE2T3lMulns7A32Jh6QzAIERv4ehCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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