SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b471ab58bb9520a8674ad1e0fcad04d5897ad14ad03d739e0b473f3eb5b171d' 
  AND token = 'SRLDqsk/c/qPeq83C6Ne9XNuG0iaaDFZBWphpyUJdiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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