SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80dcf49b1c09a0c7aa1b97285d1737041391ee15787630a523d92d5eefb18095' 
  AND token = 'rgtX3GjQsrCR0asurPZkdm4NtJdSb/DO/YAHfC7mD+g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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