SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aafc5d06967e884696ef99a90f43b087275c66cc2537351e4ddea3f26c61a807' 
  AND token = 'rrIojfAZkvLBg7EDUyyCobiJfRh2TIRI2w8ulMt67XU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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