SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fac9df96e9a8ad02632a11abf02d5266f916ef34a8aa393f0ba936cc70eebcff' 
  AND token = 'hvEnhPrmY7jX7cWbrADmsd89uCeKS6LKgwIWyc15HkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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