SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc1b35349d211b2413b7d31016c495a212e178fd135ede5fad5a7d6c5b74805b' 
  AND token = 'TPhQm2wwZjXclxemahEYbNtmmDJ1htDAoFWHdq1zpFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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