SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fda8364877469de42fb7270133d7b1c1f679508c8b3ec49107db02ca3a88a414' 
  AND token = '6RcQkQHP2zcVeFZjLUm5Q7uqErY7VKf1S5/+thX3B2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}