SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36ea8eed0bd3f219420e48ea422d6c5c5f687bdbad2d5926c3064488fe0093df' 
  AND token = 'VVtvxDxefoYEMsPmt+a+un+n+3kA6W4HPJogtbPimRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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