SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e277291da4b891e8dc8f116895c3766fdc10d5c6b8a34543c8d78886ceee72a1' 
  AND token = '+rDhgmiVv10nM8GEAt6O3dcNhTLTWUbfXSjC1zRJS+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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